The present disclosure describes systems, methods, and apparatus for reducing the frequency and/or severity of photophobic responses or for modulating circadian cycles by controlling light exposure to melanopsin ganglion cells in a retina over the action potential spectrum of the melanopsin cells of the human eye and a visual spectral response of the human eye. Embodiments of an optical filter are described. In one embodiment an optical filter may be configured to transmit less than a first amount of light weighted across the action potential spectrum of the melanopsin cells and to transmit more than a second amount of light weighted across the visual spectral response. Methods of manufacturing optical filters are also described.